Throw away insert.

摘要

A polygonal throw away insert (1) having a cutting edge (2), a center land (5) and a breaker groove (9) formed between the cutting edge and the center land. It is further formed with pairs of slopes (4) in the breaker groove near its noses, each pair extending obliquely at an angle of 5 - 20 degrees in symmetrical relation with each other with respect to each of the bisectors of the nose to form a ridge therebetween, breaker protrusions (6) extending from the center land toward the noses and having a tapered end, breaker walls (7) extending obliquely upwardly from the rear end of the pairs of slopes to the front end of the breaker protrusions (6), and ellipsoidal grooves formed in the breaker grooves so as to be continuous with the breaker walls.